JPH06210539A - Limit detection device - Google Patents

Abstract

PURPOSE:To provide a compact, simple-structure, excellent action reliability, and high-precision limit detection device for positioning. CONSTITUTION:When a rotary disc 31 having a U-shaped cross-sectional groove 31a is rotated, a slider 37 is guided by the U-shaped cross-sectional groove 31a to direct an outer edge of the rotary disc 31 and move linearly along the length of a limit detection plate 33 till a stopper pin planted on the U-shaped cross-sectional groove 31a is applied to the slider 37, and the limit detection plate 33 rotates about a center of a rotary shaft 35, thereby a limit sensor 39 detects displacement of a rotation end of the limit detection plate 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning device, and more particularly, to a limit detecting device for positioning a work in machining or assembling work.

[0002]

2. Description of the Related Art As a conventional technique related to the above, a limit detecting device applied to a linear feeding device 1 using a timing belt as shown in FIG. 8 is generally used. The linear feed device 1 includes a main roller 7 driven by a reversible motor 9.
The carriage 2 provided in engagement with the timing belt 10 stretched between the carriage 2 and the follower roller 8 is configured to perform linear movement, and is attached to the carriage 2 as the carriage 2 moves. Dogs 4 and 5 are limit sensors 3,
The stroke limit point of the actuator (not shown) is set by operating the actuator 6.

FIG. 9 shows an apparatus for detecting a linear feed amount by using a cam. For example, the reversible motor 9 shown in FIG.
The rotation speed of the reduction gear 13 meshing with the drive gear 12 is set to one rotation or less, and the cam 14 provided integrally with the reduction gear 13 is brought into contact with the limit sensors 15 and 16, so that the stroke of the linear motion is the same as in FIG. This is a configuration for setting a limit point.

[0004]

In the above prior art, when attempting to downsize the device in the case of FIG. 8, the cable processing of the limit sensors 3 and 6 becomes a bottleneck. That is, it becomes difficult to store the wiring cables for the limit sensors 3 and 6 in the limited space required for the movement of the carriage 2 inside the device. The space is not limited as long as the wiring cable is stretched outside the device, but there is a design drawback. In the case of FIG. 9,
Since it is necessary to reduce the peripheral speed of the cam 14,
The detection operation of the limit sensors 15 and 16 due to the pressing of is unstable or the adjustment is delicate, and there is a possibility of malfunction. It is an object of the present invention to provide a highly accurate positioning limit detection device which is small in size, simple in structure, and excellent in operational reliability.

[0005]

[Means for Solving the Problems] Means for solving the above problems are described in the claims. That is, the object of the present invention is to provide a rotating disk having a U-shaped cross-section groove that is continuous in a spiral shape from the center toward the outer edge, and to be provided in parallel with the surface of the rotating disk so as to face the U-shaped cross-section groove of the rotating disk. A limit detecting plate, a slider fitted to the U-shaped cross-section groove and slidably provided in the longitudinal direction of the limit detecting plate, and the limit detecting plate pivoted about a pivot shaft. A fixed plate that supports the limit detection plate, an elastic member that supports the limit detection plate at a neutral position with respect to the fixed plate, stopper pins that are planted in the U-shaped groove, and both ends of the limit detection plate in the longitudinal direction. The detection means provided in the vicinity of the slider, and the limit generated by bringing the stopper pin into contact with the slider when the slider is displaced in the longitudinal direction. It is achieved by the limit detection device and detecting the displacement of the rotating end of the output plate.

[0006]

With the above construction, with the rotation of the rotating disk, the slider is guided by the U-shaped cross-section groove and linearly moves along the longitudinal direction of the limit detecting plate toward the outer edge of the rotating disk, and the stopper pin slides. The limit detection plate rotates about the rotation axis by contacting with, and the detection means can detect the displacement of the rotation end of the limit detection plate.

[0007]

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a plan view showing an embodiment of the limit detection device of the present invention, and FIG. 2 is a side view of the same. In FIGS. 1 and 2, a rotary disk 31 (see FIG. 3) having a configuration in which a U-shaped cross-section groove 31a is formed in a spiral shape extending from the center of the disk surface to the outer edge is supported by a rotary shaft 41 and is driven to rotate. The shaft 41 is connected to a motor shaft of a drive system (not shown), a rotary shaft of a reduction gear, etc., and is rotationally driven in the direction of arrow A or arrow B. Rotating disk 3
A limit detection plate 33 and a fixed plate 32 are arranged at the closest positions parallel to the surface of the U-shaped cross-section groove 31a of FIG. The limit detection plate 33 and the fixed plate 32 are engaged with each other via a rotary shaft 35. That is, as shown in FIG. 2, the lower end of the rotary shaft 35 is fixed to the limit detection plate 33 by means such as caulking, and the other end is a bearing portion 34 provided at the center of the fixed plate 32.
And is loosely fitted. The fixing plate 32 is connected to an external member (not shown) through the mounting holes 32a.

A slider 37 is provided so as to be fitted in a slide groove 36 provided on the limit detection plate 33, and a pin 37a protruding from the slider 37 has a pin 37a which is opposed to the rotary disk 3.
The relative position is set so as to be loosely fitted in the U-shaped cross-section groove 31a. Therefore, when the rotary disk 31 performs the rotational movement in the forward and reverse directions in the arrow A or B direction, the pin 37a slides along the U-shaped cross section groove 31a. At this time, the slider 37 fitted into the slide groove 36 of the limit detection plate 33 is regulated by the slide groove 36 and converted into a linear movement in the arrow C or D direction. That is, one pitch per rotation of the rotating disk 31, that is, p
Will only move. In this way the rotating disk 31
The rotational movement amount of is decelerated and converted into a minute linear movement amount.

Both wings of the fixed plate 32 and the limit detecting plate 33 are supported in a neutral position by a pair of springs 31, 31. Thereby, in order to rotate the limit detection plate 33 in the arrow A direction or the arrow B direction with respect to the fixed plate 32 about the rotation shaft 35, an external force that opposes the biasing force of either one of the springs 31 is used. Need to be added. In the present embodiment, the limit detection plate 3 is utilized by utilizing the turning force applied to the limit detection plate 33 in the arrow A direction or the arrow B direction.
Limit sensors 3 provided close to both ends in the longitudinal direction of 3
It is configured so that 9, 40 can be operated.

FIG. 3 is a plan view showing the surface of the rotary disk 31 on which the U-shaped groove 31a is formed. As shown, the rotating disk 31
A stopper pin 42a is planted at the end of the U-shaped cross section groove 31a near the center, and a stopper pin 42b is planted at the end of the U-shaped cross section groove 31a near the outer circumference. Reference numeral 43 denotes a screw hole, which is appropriately provided in the middle of the U-shaped cross section groove 31a, similarly to the both end portions of the U-shaped cross section groove 31a, into which the stopper pin 42b is screwed. FIG. 4 is an external view of the stopper pin 42b.

FIG. 5 is a perspective view showing the fitting of the U-shaped cross section groove 31a and the pin 37a and the operating state of the limit sensor 39. The limit detecting operation in the above configuration will be described with reference to FIGS. 1, 2 and 5. The drive system causes the rotary drive shaft 41 to move in the counterclockwise direction (arrow A in FIGS. 1 and 5).
Direction), the slider 37
Moves in the direction of arrow C, and the stopper pin 42b shown in FIG. 5 comes into contact with the pin 37a at the end of the movement.
At this time, the stopper pin 42a continues to move to the pin 3
7a is pressed in the direction of arrow A.
7 → Limit detection plate 33 → Limit sensor 39
The limit detection plate 33 rotates in the direction of arrow A about the rotation shaft 35 against the urging force of the spring 39 to operate the limit sensor 39.

FIG. 6 is a perspective view showing an operating state of the limit sensor 40 when the rotary drive shaft 41 rotates clockwise (direction of arrow B). When the rotary drive shaft 41 rotates clockwise (direction of arrow B), the slider 37 moves in the direction of arrow D, and the stopper pin 42a implanted near the center of the rotary disk 31 presses the pin 37a. The pressing force is transmitted in the order of the slider 37, the limit detection plate 33, and the limit sensor 40. Other operations follow the counterclockwise direction shown in FIG.

As described above, according to this embodiment, the rotating disk 3
The rotary motion of 1 is converted into the linear motion of the slider 37, and the slider 37 can operate the limit sensor 39 or 40 at both ends of the linear motion. As shown in FIG. 7, the center O of the rotary shaft 35 and the stopper pin 4 are
2b and the distance R from the center O of the rotary shaft 35 to the operating point of the limit sensor 39 are set to appropriate values, whereby the operating speed with respect to the limit sensor 39 in the counterclockwise rotation of the rotating disk 31 ( It is also possible to adjust the pressing force), and it is preferable to select it according to the characteristics of the limit sensor used. For example, in the above embodiment, the limit sensor 39 represents a photoelectric or non-contact type switch, and the limit sensor 40 represents a so-called micro switch, but the above-mentioned proper use does not have a special meaning. Any type of sensor may be used on either side. Incidentally, in the embodiment, the shape of both end portions of the plate for limit detection 33 is shown to correspond to the type of sensor or switch which is the opposite hand. The same applies to the case of the stopper pin 42a and the limit sensor 40 in the clockwise rotation. According to the present embodiment, the rotational peripheral speed of the rotary drive shaft 41 on the drive side is significantly reduced and converted into a linear displacement amount, and a minute displacement is obtained in the linear direction. Since the operation of the plate 33 acts in the direction perpendicular to the longitudinal direction of the limit detection plate 33 and is independent of the direction of displacement, the operation of the limit sensor 39 or 40 is stable and there is no risk of malfunction. It has excellent effects such as highly reproducible operation efficiency that was not available in the technology. In addition, by arbitrarily providing the mounting position of the stopper pin 42 at a position other than both end portions, various strokes can be selected, and the side effect that the limit detection device can be standardized can be achieved.

[0014]

By implementing the present invention, it is possible to reduce the size of the device by integrally forming the positioning movement part and the limit detection operation part, and to increase the operation speed of the means for detecting the positioning limit, that is, the limit sensor. In addition, it is possible to provide a limit detection device that is highly reliable and has a stable detection operation that is easily adjusted.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a limit detection device of the present invention.

FIG. 2 is a side view showing an embodiment of the limit detection device of the present invention.

FIG. 3 is a plan view showing a surface on which a U-shaped cross-section groove of the rotary disc shown in FIG. 1 is provided.

FIG. 4 is an external view of a stopper pin in FIG.

5 is a perspective view showing an engagement state of a U-shaped cross section groove and a pin in FIG. 1 and an operating state of a limit sensor.

FIG. 6 is a perspective view showing an operating state when the rotary drive shaft in FIG. 6 rotates clockwise.

FIG. 7 is an operation relationship diagram of the slider and the limit sensor in FIG.

FIG. 8 is a side view of a limit detection device applied to a conventional linear feed device.

FIG. 9 is a plan view of another conventional limit detection device.

[Explanation of symbols]

1 ... Linear feeder 2 ... Carriage 3, 6 ... Limit sensor 4, 5 ... Dog 7 ... Lead pulley 8 ... Follower pulley 9 ... Reversible motor 10 ... Timing belt 11 ... Guide rod 12 ... Drive gear 13 ... Reduction gear 14 ... Cams 15 and 16 ... Limit sensor 31 ... Rotating disk 31a ... U-shaped cross section groove 32 ... Fixed plate 32a ... Mounting hole 33 ... Limit detection plate 34 ... Bearing part 35 ... Rotating shaft 36 ... Slide groove 37 ... Slider 37a ... Pin 38 ... Spring 39, 40 ... Limit sensor 41 ... Rotation drive shaft 42 ... Stopper pin 43 ... Screw hole

Claims (1)

[Claims] 1. A rotary disc having a U-shaped cross-section groove continuous from the center toward the outer edge in a spiral shape, and for limit detection provided opposite to the U-shaped cross-section groove of the rotary disc and parallel to the rotary disc surface. A plate, a slider fitted in the U-shaped cross-section groove and slidable in the longitudinal direction of the limit detecting plate, and supporting the limit detecting plate rotatably about a rotation axis. Fixing plate, an elastic member that supports the limit detecting plate in a neutral position with respect to the fixing plate, a stopper pin that is planted in the U-shaped cross-section groove, and is close to both ends in the longitudinal direction of the limit detecting plate. And a detection means provided on the slider, the limit detection probe being generated by bringing the stopper pin into contact with the slider when the slider is displaced in the longitudinal direction. Limit detection unit and detecting the displacement of the rotating end of the over bets.